Articles - Chemical Science & Engineering Research

Abstract

This work is aimed at the comparison of sorption of Pb²⁺ from aqueous solution using Gmelina sawdust and Zn-Oxalic acid (Zn-OXA) framework. Gmelina sawdust biosorbent was prepared by carbonization and subsequently activated; whereas, the Zn-OXA framework sorbent was prepared using slow evaporation method. These materials were characterised using FTIR. The analysis revealed principally the presence of COOH, C=O, CHO, C(O)-O-C and most likely amine functional groups in the biomaterials. The decrement in the FTIR absorption value of O-H and C = O of oxalic acid as observed in the Zn-OXA framework clearly implied that oxalic acid bonded to the Zn²⁺ ion via O - H and C= O functional groups. It was observed that the removal of Pb²⁺ by these adsorbents is: Zn-OXA framework (95%) < un carbonised sawdust (96.67%) < carbonized sawdust (99%). The multifunctionalities and may be higher porosity for the sawdust biosorbent is likely the reason it has performed better than Zn-OXA framework in terms of the Pb²⁺ adsorption. However, both the sawdust product and Zn-OXA framework are effective in the sorption of the Pb²⁺ from aqueous solution.